1. Field of the Invention
The present invention relates to lighting systems that are digitally controlled and to the light fixtures used therein, and more particularly to such lighting systems as well as to multiparameter lights that have an image projection lighting parameter and a camera and that are useful in such lighting systems.
2. Description of the Related Art
Lighting systems are formed typically by interconnecting many light fixtures by a communications system and providing for operator control from a central controller. Such lighting systems may contain multiparameter light fixtures, which illustratively are light fixtures having individually remotely adjustable parameters such as beam size, color, shape, angle, and other light characteristics. Multiparameter light fixtures are widely used in lighting industry because they facilitate significant reductions in overall lighting system size and permit dynamic changes to the final lighting effect. Applications and events in which multiparameter light fixtures are used to great advantage include showrooms, television lighting, stage lighting, architectural lighting, live concerts, and theme parks. Illustrative multi-parameter light devices are described in the product brochure entitled xe2x80x9cThe High End Systems Product Line 2001xe2x80x9d and are available from High End Systems, Inc. of Austin, Tex.
Prior to the advent of relatively small commercial digital computers, remote control of light fixtures from a central controller was done with either a high voltage or low voltage current; see, e.g., U.S. Pat. No. 3,706,914, issued Dec. 19, 1972 to Van Buren, and U.S. Pat. No. 3,898,643, issued Aug. 5, 1975 to Ettlinger. With the widespread use of computers, digital serial communications over wire was widely adopted as a way to achieve remote control; see, e.g., U.S. Pat. No. 4,095,139, issued Jun. 13, 1978 to Symonds et al., and U.S. Pat. No. 4,697,227, issued Sep. 29, 1987 to Callahan. In 1986, the United States Institute of Theatre Technology (xe2x80x9cUSITTxe2x80x9d) developed a digital communications system protocol for multi-parameter light fixtures known as DMX512. Basically, the DMX512 protocol consists of a stream of data which is communicated one-way from the control device to the light fixture using an Electronics Industry Association (xe2x80x9cEIAxe2x80x9d) standard for multipoint communications know as RS-485.
A variety of different types of multiparameter light fixtures are available. One type of advanced multiparameter light fixture which is referred to herein as an image projection lighting device (xe2x80x9cIPLDxe2x80x9d) uses a light valve to project images onto a stage or other projection surface. A light valve, which is also known as an image gate, is a device such as a digital micro-mirror (xe2x80x9cDMDxe2x80x9d) or a liquid crystal display (xe2x80x9cLCDxe2x80x9d) that forms the image that is projected. U.S. Pat. No. 6,057,958, issued May 2, 2000 to Hunt, discloses a pixel based gobo record control format for storing gobo images in the memory of a light fixture. The gobo images can be recalled and modified from commands sent by the control console. U.S. Pat. No. 5,829,868, issued Nov. 3, 1998 to Hutton, discloses storing video frames as cues locally in a lamp, and supplying them as directed to the image gate to produce animated and real-time imaging. A single frame can also be manipulated through processing to produce multiple variations. Alternatively, a video communication link can be employed to supply continuous video from a remote source.
U.S. Pat. No. 5,828,485, issued Oct. 27, 1998 to Hewlett, discloses the use of a camera with a DMD equipped light fixture for the purpose of following the shape of the performer and illuminating the performer using a shape that adaptively follows the performer""s image. The camera taking the image preferably is located at the lamp illuminating the scene in order to avoid parallax. The image can be manually investigated at each lamp or downloaded to some central processor for this purpose. This results in a shadowless follow spot.
While the type of light fixture that provides a shadowless follow spot function and while the type of light fixture that stores images internally for projection have value in the lighting industry, these types of light fixtures and/or the lighting systems in which they operate all limit the operator of the lighting system to carrying out image projection operations on the basis of individual light fixtures. Moreover, having to store images at the light fixture is very limiting to the user of the device, since the operator must upload images to the light fixture from a computer before placing the light fixture into service.
These and other disadvantages of the prior art are overcome in one or more embodiments of the present invention by supporting two or more channels of content in digital form, including content such as image content, over one communications path for projection by multiple IPLDs in a lighting system, or by supporting a command channel and at least one channel of content in digital form, including content such as image content, over one communications path for projection by at least one IPLD in a lighting system. The term xe2x80x9cimagexe2x80x9d is a general term that refers to a wide variety of image types, including continuous video images such as movies, graphic effects, and news programs, and still images such as pictures and clip art. In this way, one or more IPLDs on the same communications system may be supplied with one or more different channels of image content while at the same time being able to respond to commands, thereby giving the operator of the lighting system enormous creative control with regard to the image content projected by the various IPLDs in the system. The term xe2x80x9ccontentxe2x80x9d is a general term that refers to various types of creative works, including image-type works and audio works.
One embodiment of the present invention is a lighting system comprising a central controller, a digital communications path, and a plurality of image projection lighting devices. The digital communications path comprises a plurality of content transfer channels having respective unique content transfer channel addresses and being individually selectable in accordance with the content transfer channel addresses thereof. The plurality of image projection lighting devices have respective unique device addresses and are interconnected by the digital communications path for communicating content on a selected one or more of the content transfer channels in response to commands from the central controller.
Another embodiment of the present invention is a lighting system comprising a first digital communications path compliant with a DMX protocol; a second digital communications path having a bandwidth sufficient for transferring content in digital form; a plurality of light fixtures interconnected by the first digital communications path, the light fixtures including a plurality of image projection lighting devices having respective unique device addresses and being interconnected by both the first and second digital communications paths; and a DMX controller interconnected with the light fixtures by the first digital communications path. The second digital communications path is a bidirectional path comprising a plurality of addressable content transfer channels individually selectable by the DMX controller in accordance with the addresses thereof.
Another embodiment of the present invention is a multiparameter light comprising an internal control system, a light valve, an image control interface coupling the light valve to the internal control system, and a communications port coupled to the internal control system. The internal control system comprises a component for recognizing a unique device address received at the communications port on a control channel, and a component for selectively accessing a plurality of content transfer channels having respective unique content transfer channel addresses to communicate content in digital form thereon in response to receipt of the unique device address and at least one of the content transfer channel addresses at the communications port on the control channel.
Another embodiment of the present invention is a method of controlling a lighting system comprising a digital communications path with a bandwidth sufficient for communicating a plurality of content signals in digital form on respective transfer channels having respective unique channel addresses, and a plurality of image projection lighting devices interconnected by the digital communications path and having respective unique device addresses. The method comprises selecting a first one of the image projection lighting devices by the unique device address thereof; accessing with the first image projection lighting device a first one of the transfer channels of the digital communications path by the unique channel address thereof; carrying a first content signal over the digital communications path on the first transfer channel during at least part of the first image projection lighting device accessing step; selecting a second one of the image projection lighting devices by the unique device address thereof; accessing with the second image projection lighting device a second one of the transfer channels of the digital communications path by the unique channel address thereof; and carrying a second content signal over the digital communications path on the second transfer channel during at least part of the second image projection lighting device accessing step.
A further embodiment of the present invention is a lighting system comprising a central controller; an image projection lighting device comprising a housing, a light valve contained within the housing, and at least one communications connector mounted to the housing; and a digital communications path comprising a plurality of content transfer channels having respective unique content transfer channel addresses, the digital communications path being coupled to the central controller and further being coupled to the image projection lighting device via the communications connector.
Another embodiment of the present invention is a lighting system comprising a central controller; an image projection lighting device comprising a housing, a light valve contained within the housing, an external video input mounted to the housing, an external audio input mounted to the housing, and at least one communications connector mounted to the housing; and a digital communications path comprising a plurality of content transfer channels having respective unique content transfer channel addresses, the digital communications path being coupled to the central controller and further being coupled to the image projection lighting device via the communications connector.